Diaphragm Based Spontaneous Inflation Inhibitor in a Pump for an Inflatable Prosthesis

ABSTRACT

A method of preventing inadvertent inflation of an implantable prosthetic includes biasing a valve assembly such that an outlet is substantially closed and using inadvertent pressure increases from the inlet to supplement the biasing of the valve assembly. It may further include the step of preventing fluid flow through the outlet by selectively varying fluid pressure within a bypass passageway having a first end which is in fluid communication with an inlet and a second end which is in fluid communication with a chamber. And, may also additionally include the step of displacing a flexible abutting wall disposed between the chamber and the valve assembly so that the abutting wall is caused to contact the valve assembly and urge the valve assembly into a closed position when the fluid pressure within the chamber exceeds a predetermined amount.

REFERENCE TO RELATED APPLICATIONS

The present application is a divisional patent application of U.S. Ser.No. 10/821,232, filed Apr. 8, 2004, now U.S. Pat. No. 7,438,682, whichis a divisional patent application of U.S. Ser. No. 10/010,498, filedDec. 3, 2001, now U.S. Pat. No. 6,730,017, which claims priority to U.S.Prov. Ser. No. 60/295,326, filed Jun. 1, 2001 and is also acontinuation-in-part patent application of U.S. Ser. No. 09/749,292,filed Dec. 27, 2000, now abandoned. Each of the identified patentapplications and patents are hereby incorporated by reference.

BACKGROUND

This invention generally relates to a pump and valve assembly forinflating a prosthesis. More particularly, the invention relates topressure based mechanisms that inhibit spontaneous inflation of theprosthesis, including stiffening and support mechanisms that alsoimprove the function of the valve.

One common treatment for male erectile dysfunction is the implantationof a penile prosthesis. Such a prosthesis typically includes a pair ofinflatable cylinders which are fluidly connected to a fluid (typicallyliquid) reservoir via a pump and valve assembly. The two cylinders arenormally implanted into the corpus cavernosae of the patient and thereservoir is typically implanted in the patient's abdomen. The pumpassembly is implanted in the scrotum. During use, the patient actuatesthe pump and fluid is transferred from the reservoir through the pumpand into the cylinders. This results in the inflation of the cylindersand thereby produces the desired penis rigidity for a normal erection.Then, when the patient desires to deflate the cylinders, a valveassembly within the pump is actuated in a manner such that the fluid inthe cylinders is released back into the reservoir. This deflation thenreturns the penis to a flaccid state.

With inflatable penile prostheses of current designs, spontaneousinflation of the cylinders is known to occasionally occur due toinadvertent compression of the reservoir, resulting in the undesiredintroduction of fluid into the cylinders. Such inadvertent inflation canbe uncomfortable and embarrassing for the patient. This undesirablecondition is further described below with reference to a particularprosthetic design.

With reference to FIG. 1, a known pump and valve assembly 8 for use in apenile prosthesis includes a fluid input 10 that is coupled at one endto a reservoir (not shown) and to a housing 12 at its opposite end. Alsoconnected to the housing 12 is a fluid output 14 which, in turn, isconnected at its other end to a pair of cylinders (not shown). Linkingthe fluid input 10 and the fluid output 14 to each other is a commonpassageway 33, which itself contains a valve assembly that is describedin greater detail below. Common passageway 33 is also in fluidcommunication with a pump bulb 18 that is used to move fluid from thereservoir (not shown) to the cylinders (not shown) in order to inflatethe cylinders. The valve assembly located within common passageway 33includes a reservoir poppet 20 which is biased against a valve seat 24by a spring 28 and a cylinder poppet 22 which is biased against a valveseat 26 by a spring 30. The springs 28 and 30 are sized so as to keepthe reservoir poppet 20 and the cylinder poppet 22 biased against eachrespective valve seat 24 and 26 under the loads that are encounteredwhen the reservoir is pressurized to typical abdominal pressures.

When the patient wishes to inflate the cylinders, pump bulb 18 issqueezed so as to force fluid from the pump bulb 18 into the commonpassageway 33. The resulting fluid flow serves to reinforce the forcefrom the spring 28 urging the reservoir poppet 20 against valve seat 24while at the same time causing compression of the spring 30, and therebyopening cylinder poppet 22. As a result, the fluid travels out throughfluid output 14 and into the respective cylinders.

When the patient releases the pump bulb 18 a vacuum is created, thuspulling the poppet 22 back against valve seat 26 (aided by spring 30)and simultaneously pulling the reservoir poppet 20 away from its valveseat 24, against the spring 28. As a result, fluid from the reservoir isthus allowed to flow through the fluid input 10 and into the commonpassageway 33 passing around the reservoir poppet 20 and into thevacuous pump bulb 18. Once the pump bulb 18 has been filled, thenegative pressure is eliminated and the reservoir poppet 20 returns toits normal position. This pumping action of the pump bulb 18 and valveassembly is repeated until the cylinders are fully inflated.

To deflate the cylinders, the patient grips the housing 12 andcompresses it along the axis of reservoir poppet 20 and cylinder poppet22 in a manner such that the wall 13 of the housing 12 contacts theprotruding end 21 of the reservoir poppet 20 and forces the reservoirpoppet 20 away from valve seat 24. This movement, in turn, causes thereservoir poppet 20 to contact cylinder poppet 22 and force cylinderpoppet 22 away from valve seat 26. As a result, both poppets 20 and 22are moved away from their valve seats 24 and 26 and fluid moves out ofthe cylinders, through the fluid output 14, through common passageway33, through the fluid input 10 and back into the reservoir.

Although the springs 28 and 30 are sized to provide sufficient tensionto keep poppets 20 and 22 firmly abutted against valve seats 24 and 26under normal reservoir pressures, it is possible that pressure thatexceeds the force provided by the springs could be exerted upon thereservoir during heightened physical activity or movement by thepatient. Such excessive pressure on the reservoir may overcome theresistance of the spring-biased poppets 20 and 22 and thereby cause aspontaneous inflation of the cylinders. After implantation,encapsulation or calcification of the reservoir may occur. Encapsulationor calcification of the reservoir can lead to additional problems. Inparticular, the encapsulation could lead to a more snugly enclosedreservoir, thus increasing the likelihood of spontaneous inflation.

In previous attempts to reduce or eliminate the occurrence ofspontaneous inflation, different types of spontaneous inflationpreventing valves have been introduced into the pump and valve assembly.Such previous valves are intended to permit the positive flow of fluidto the cylinders only in those circumstances when the patient hasforcibly manipulated the valve.

Although such previous valve designs reduce the frequency of spontaneousinflation, several drawbacks do exist. For example, such valves aretypically complex, requiring two-handed operation which is a seriousdrawback to elderly or severely ill patients. Some spontaneous inflationpreventing valves also require the application of excessive force inorder to manipulate the valves; which may be too demanding for somepatients. Furthermore, such valve designs may cause patient discomfortdue to the valve size or shape, because of increase in the overallvolume of the implant within the patient. This increased size can alsolead to interference with the patient's normal bodily functions. Suchprevious valve designs typically add undesirable cost to the device aswell as increase the complexity of the surgical implantation procedure.

A solution to the above-identified drawbacks is disclosed in co-pendingU.S. patent application Ser. No. 09/749,292 entitled “PRESSURE BASEDSPONTANEOUS INFLATION INHIBITOR” which is assigned to the Assignee ofthe present invention and is incorporated herein by reference. However,the operational efficiency of the prosthesis pump could be furtherimproved by optimizing the operative manipulation of the assembly.

Presently, the pump and valve assemblies used in implantable prosthesesshare certain characteristics. A compressible pump bulb is attached tothe housing and is in fluid communication with the various fluidpathways. In order to inflate the cylinders, the compressible pump bulbis actuated by the patient, thereby urging fluid past the poppets intothe cylinders. In order to deflate the cylinders, the valve housing isgrasped and squeezed (through the patient's tissue), causing the poppetsto unseat and allow fluid to flow back to the reservoir.

Since the pump and valve assembly is positioned within the patient'sscrotum, the various components of the assembly must be small. As aresult, manipulation of the pump and valve assembly is sometimesdifficult. For example, patients requiring the use of a penileprosthesis are oftentimes elderly and have a reduced dexterity as aresult of aging. Thus, in some instances, even locating the devicewithin the tissue can be a challenge, let alone identifying the correctportion of the assembly to actuate. More specifically, with somepatients it may be difficult to determine whether the housing portion ofthe assembly that leads to release or deflation of the cylinders isbeing grasped, or whether the bulb portion which would be used toinflate the cylinders is being grasped.

Notably, the length of the valve assembly is determined (at least in onedirection) by the size of the various poppets and the distance suchpoppets must move in order to open and close the various fluidpassageways. As a result, such a pump and valve assembly typically islonger in a direction parallel with the poppets. Moreover, in order torelease the poppets in an assembly configured in this manner, thepatient must grasp the narrower, shorter sidewalls of the assembly andcompresses them together. Such a configuration can present challengesinsofar as the spring tension of the poppets at the time of desireddeflation is typically at a maximum while the surface area of theassembly which must be compressed in order to cause such deflation is ata minimum. This condition can lead to a situation where the patient hasdifficulty actually compressing the assembly, or in extremecircumstances, actually loses grip of the assembly during such attemptsat deflation.

There exists a need for an improved prosthetic penile implant having aspontaneous inflation prevention mechanism that affords convenientoperative manipulation by a patient.

SUMMARY OF THE INVENTION

The present invention includes a penile pump having a dual poppetarrangement wherein the poppets act as check valves or flow valves. Eachpoppet is spring-biased against a valve seat, and under normalcircumstances, only allows positive fluid flow when a pump bulb isoperated, thus causing an increase in fluid pressure which istransferred to the inflatable cylinders. To prevent spontaneousinflation when an overpressurization occurs in the reservoir, the samereservoir pressure is utilized to seal the fluid output against itselfor to seal one or both of the poppets against the valve seat. Thus, thefluid is prevented from reaching the cylinders and creating aspontaneous inflation. When the movement or activity generating theoverpressure in the reservoir is released, the system should return toequilibrium. Even if overpressurization of the reservoir is occurring,the pressure generated by compressing the pump bulb will far exceed thelevel of overpressure. Thus, the poppets will open in the normal way,allowing fluid to flow to the cylinders. The use of the overpressure inthe reservoir itself to prevent fluid flow to the cylinders can occur ina variety of formats.

In still another embodiment, the reservoir poppet is actually coupled toan outer wall defining a portion of the fluid input. When anoverpressurization in the reservoir occurs, this outer wall is forced toexpand which simultaneously causes the reservoir poppet to be pulledfirmly against the valve seat. This effectively prevents fluid flow fromreaching the cylinders and causing a spontaneous inflation.

In yet another embodiment of the present invention, the valve seat isprovided with a flexible valve which cooperates with the first poppet toprevent spontaneous inflation which could be caused by excessivepressure in the reservoir. Specifically, pressure in the reservoir andassociated valve input is presented to the flexible valve and thuscausing the valve to be further forced against the poppet, thus sealingoff the input. When inflation is desired however, the negative pressurepulling the first poppet away from the valve seat will allow the desiredfluid flow.

In yet still another embodiment, a tapered poppet is utilized inconjunction with a tapered valve seat. Each of these tapers do notexactly match each other, thus providing variable reactions to pressuresignals.

In a further embodiment, a section of the reservoir poppet protrudesinto the reservoir chamber. This protruding section of the reservoirpoppet is coupled to the outer wall of the reservoir chamber. The poppetis coupled to the wall with a connecting spring that permits relativemovement between the poppet and the outer wall. The tension of thespring is selected so that it approximates the forces generated bypressurized fluid acting on the wall of the reservoir chamber. However,the spring force is not so great as to prevent the vacuum generated bythe pump bulb from opening the poppet. Thus, when the pump bulb iscompressed and released, the vacuum forces generated are sufficient tounseat to the reservoir poppet despite its connection to the outerreservoir chamber wall.

In yet still a further embodiment, a relatively large and powerfulbiasing spring is coupled with the reservoir poppet to exert arelatively large force against the reservoir poppet forcing it into asealing or closed position. Due to the strong biasing forces of thespring, overpressurization forces generated in the reservoir chamber areinsufficient to unseat the reservoir poppet. Simply using such a springwill make it difficult for the vacuum forces generated by compression ofthe pump bulb to unseat the reservoir poppet. To eliminate this problem,the face of the reservoir poppet, which forms a fluid-tight seal whenthe reservoir poppet is in a closed position, is made relatively large.That is, the diameter of the face approaches the diameter of the chambercontaining the reservoir poppet. Thus, the vacuum forces generated willact over a larger surface area thereby exerting a larger degree offorce, which permits the unseating of the reservoir poppet despite theopposing force of the biasing spring.

Because it is difficult to fabricate a housing having a planar wall thatinteracts with the planar poppet face to form a sufficiently fluid-tightseal, the portion of the housing holding the reservoir poppet contains apair of spaced lip seals. The position of the lip seal serves twodistinct purposes. The first is to prevent fluid pressure generatedduring over pressurization of the reservoir from engaging a largeportion of the poppet face, which would in effect defeat the addedstrength provided by the biasing spring. The outer seal is also providedso that when a vacuum force is generated, the vacuum cannot act on thefront surface of the poppet face which would, in effect, hold thereservoir poppet in a closed position.

In another embodiment of the present invention, the reservoir poppet isconfigured with a throughbore at a rear portion of the reservoir poppetthat is in fluid communication with a passageway and an outlet adjacentto the cylinder poppet. A sliding valve seal is positioned over thissection of the reservoir poppet. The sliding valve seal is held againstthe back wall of the chamber by a spring positioned between the frontface of the sliding valve seal and the back face of the suction poppetvalve seal. The arrangement of the valve sleeve on the rear of thereservoir poppet is such that fluid is only able to flow through thethroughbore and out of the outlet when the valve sleeve is positionednear the rear of the chamber and the front face of the reservoir poppetis firmly seated. In a reservoir overpressurization situation, the valvesleeve is again pressed against the rear of the chamber. However, thereservoir poppet is also forced backwards into the chamber, forcing thethroughbore to be occluded by the valve sleeve. This prevents fluid fromflowing towards the cylinder poppet which could ultimately lead tospontaneous inflation.

In yet another embodiment, the portion of the housing between thecylinder poppet and the reservoir chamber has been modified. Inaddition, the reservoir poppet is provided with a unique configurationto interact with the housing structure. The reservoir poppet has a face,similar to the other embodiments, that is spring biased towards amatching valve seat. An annular ring is molded into the housing justbehind (towards the cylinder poppet) the valve seat and is sized tointeract with the face.

The pump assembly of this embodiment has two states, activated anddeactivated. In the activated state, the reservoir poppet is positionedso that the face is between the annular ring and the valve seat. When sopositioned, the pump assembly functions as previously described withreference to the other embodiments. A compression of the pump bulb forcethe face against the valve seat and causes the cylinder poppet to open.A release of the pump bulb generates a vacuum which removes thereservoir poppet face from the valve seat and allows fluid to flow fromthe reservoir and into the pump bulb. Thus, the activated state is usedwhen actively inflating the cylinders and while it is desired tomaintain the cylinders in an inflated state.

In the deactivated state, the reservoir poppet is positioned so that theface moves through the annular ring. In this position, the face will bebetween the cylinder poppet and the annular ring and the reservoirpoppet spring will bias the face so that it abuts the annular ring. Inother words, the face is displaced from the valve seat, and a gap existsbetween the valve seat and the annular ring. The stem of the reservoirpoppet extends from the face towards the cylinder poppet. The stem is acylindrical member having a generally V-shaped groove extending aboutits circumference near the middle of the stem. The stem interacts with aflexible conical lip seal molded within the housing. When in theactivated state, the conical lip seal is positioned near the V-shapedgroove so that fluid flow is essentially unhindered. When in thedeactivated state, the conical lip seal is caused to engage thecylindrical portion of the stem. Thus, a fluid tight seal can be formed.

When in the deactivated state, the reservoir poppet can be moved toengage and release the cylinder poppet, leading to a deflation of thecylinders. During this time, the conical lip seal continues to belocated near the cylindrical portion of the stem; however, the flexiblenature of the conical lip seal allows fluid flow in a direction from thecylinders to the reservoir. The pump assembly must be placed in thedeactivated state to prevent spontaneous inflation. When in this state,the conical lip seal engages the cylindrical portion of the stem. Ifoverpressure is generated, the reservoir poppet can be displaced towardsthe cylinder poppet. As this occurs, the increased fluid pressure levelsforce the conical lip seal to firmly abut the cylindrical portion of thestem, preventing increased pressure levels from reaching and displacingthe cylinder poppet. Thus, spontaneous inflation is prevented.

To further improve the operational efficiency of the pump and valveassembly, in yet still another embodiment, a reservoir poppet is made ofa metal material with a plastic member disposed over a segment of themetal material. The plastic segment of the reservoir poppet preventsundesired frictional contact (metal on metal) with other metal members,and prevents premature wearing of the contact point of the twocomponents.

In another embodiment, a pump and valve assembly includes a pump bulbthat is differentiated from the valve housing when inflation of thecylinders is desired. To supplement differentiation between the bulb andthe valve housing, the valve housing is provided with a textured surfaceso that even through tissue the patient is able to readily discern whicharea comprises the pump bulb and which area comprises the valve housing.This is important in that the pump bulb is compressed for inflationwhile the valve housing is compressed for deflation.

The pump assembly is configured such that it has a length longer thanits width, with its internal poppets running parallel with the length.To release fluid from the inflated cylinders, the internal poppets areactuated so that they move in a direction parallel to the length, untilthey open. To achieve this action directly, the opposing sides of thewidth of the valve housing are compressed. This compression causesactuation of the internal poppets.

In addition, an actuating bar is positioned within the valve housingparallel with and extending along at least one of the sides of thelength. An arm attached to the actuating bar extends along a portion ofone of the sides of the width in close proximity to the tip of one ofthe poppets. Thus, the configuration of the actuating bar causes it toengage and open the poppet allowing fluid to flow from the cylinder tothe reservoir. Furthermore, the patient can grasp the valve housing invirtually any orientation and when pressure is applied, the actuatingbar will act either directly or indirectly to open the appropriatepoppets. Thus, so long as the patient grasps any portion of the pump andvalve assembly other than the pump bulb, compression will result in thedesired opening of the poppets which allows the cylinders to deflate.

Furthermore, since the patient can grasp the valve housing along thesides of the length, i.e., surfaces with larger surface area, lesspressure need be applied to achieve the successful opening of thepoppets. In other words, by increasing the surface area that is engagedby the patient's fingers and appropriately positioning the actuatingbar, less force need be exerted by the patient to achieve the desiredresult.

The textured surface of the valve housing not only helps the patientidentify the correct portion of the pump and valve assembly to actuate,it also serves to prevent slippage once the patient begins to compressthe housing. Thus, what is achieved is an efficient and ergonomic pumpand valve assembly for an implantable prosthesis. The pump and valveassembly can advantageously be formed from a minimal number ofcomponents. That is, all that need be molded are a valve block and acorresponding pump bulb which surrounds the valve block. The variouspoppets can be inserted into the valve block and then placed within theinterior of the pump bulb, thus forming a completed assembly. Thisresults in certain manufacturing efficiencies, thus reducing both costand time of production.

To prolong the life of the valve assembly, ribs are added to theactuating bar. The ribs increase the strength and stiffness of theactuating bar and prevent deflection during actuation. Permanentdeformation of the actuating bar is prevented when normal deflectionoccurs during actuation. As a result, full axial motion of the poppet isensured. Another rib is disposed along an actuation face of theactuating bar to also limit deformation during actuation.

To improve the ease of deflation, a stiff poppet support wraps aroundthe valve body and rests against a portion of the check valve. Thepoppet support has a shelf that provides a smooth surface for a portionof the check valve to slide. The poppet support contacts the check valveand prevents undesirable sideways movement of the check valve againstthe valve body. The positioning and configuration of the poppet supportthus allows the check valve to easily move axially into the valve bodyto an open position. This results in improved operational efficiency ofthe prosthesis pump and an extended operating life.

In most of the embodiments, the force generated by an overpressurizationof the reservoir is used to prevent fluid flow into the cylinders.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side-sectional view of a penile pump according to theteachings of the prior art.

FIG. 2 is a side-sectional view of a penile pump wherein the reservoirpoppet has been attached to an outer wall of the reservoir chamber.

FIG. 3 is a side, partially sectional planar view of the attachmentmechanism connecting the reservoir poppet to the outer wall of the fluidinput chamber.

FIG. 4 is a side sectional view of housing for a penile pump having atapered reservoir poppet and corresponding passageway which plugs thefluid input during overpressure situation.

FIG. 5 is a side sectional view of housing for a penile pump havingrelief areas which expand during an overpressure situation and sealagainst the reservoir poppet.

FIG. 6 is a side sectional view of the penile pump in FIG. 5,illustrated during an overpressure situation.

FIG. 7 is a side sectional view of the penile pump in FIG. 5,illustrated during a compression of the pump bulb.

FIG. 8 is a side sectional view of the penile pump in FIG. 5,illustrated during a reinflation of the pump bulb.

FIG. 9 is a side sectional view of the housing of a penile pump havingrelief areas which expand during an overpressure situation, and atermination chamber which cooperates with the cylinder poppet during theoverpressure situation.

FIG. 10 is a side sectional view of a housing for a penile pump having areservoir poppet coupled to the outer wall of the reservoir chamber viaa connecting spring.

FIG. 11 is a side sectional view of the penile pump of FIG. 10 during anoverpressurization situation.

FIG. 12 is a side sectional view of the penile pump of FIG. 10 whenvacuum forces are generated by the pump bulb.

FIG. 13 is a side sectional view of the penile pump of FIG. 10 when bothpoppets have been manually opened.

FIG. 14 is a side sectional view of a housing for a penile pump whereinthe reservoir poppet includes a relatively large biasing spring and alarge diameter poppet face which abuts the two-spaced lip seals.

FIG. 15 is a side sectional view of a housing for a penile pump having areservoir poppet that includes a slidable valve seal that selectivelyincludes a throughbore leading to an outlet in the reservoir poppet.

FIG. 16 is a side sectional view of the penile pump illustrated in FIG.15 during a compression of the pump bulb.

FIG. 17 is a side sectional view of the penile pump illustrated in FIG.15 when no forces are being generated.

FIG. 18 is a side sectional view of the penile pump illustrated in FIG.15 when both poppets have been manually opened.

FIG. 18A is a perspective view of an alternate embodiment of a poppetusable in the penile pump in accordance with the present invention.

FIG. 19 is a side sectional view of a penile pump assembly including aconical lip seal and an annular ring that interact with a reservoirpoppet having a grooved stem and an abutting face.

FIG. 20 is a side sectional view of the pump assembly of FIG. 19 withthe cylinder poppet unseated.

FIG. 20A is a side sectional view illustrating how the reservoir poppetmay be spaced from the annulus to effect fluid flow.

FIG. 20B is front planar view of an annulus with a plurality of spacers.

FIG. 21 is a side sectional view of the pump assembly of FIG. 19 whilethe cylinders are being deflated.

FIG. 22 is a side sectional view of the pump assembly of FIG. 19 whilein a deactivated state, which serves to inhibit spontaneous inflation.

FIG. 23A shows a side view of an alternative embodiment of the entirereservoir poppet including a plastic portion.

FIGS. 23B and 23C are more detailed illustrations of portions of thereservoir poppet, with FIG. 23B showing a poppet taper and FIG. 23Cshowing an alternative design.

FIG. 24 is an exploded perspective view of an alternative embodiment ofthe present invention.

FIG. 25 is perspective view of the actuating bar of the embodiment ofFIG. 24.

FIG. 26A is a top sectional view of the embodiment of FIG. 24.

FIG. 26B is a top sectional view of the embodiment of FIG. 24 showingthe elements in a position when both cylinders are inflated.

FIG. 26C is a top sectional view of the embodiment of FIG. 24 showingboth valves open.

FIG. 27 is a perspective view of the poppet support of the embodiment ofFIG. 24.

FIG. 28 is a sectional view of the embodiment of FIG. 24.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIG. 1, a pump assembly is shown and generally referred toas 8. The pump assembly 8, as illustrated in FIG. 1, is essentially thatof the prior art, but an understanding of the working elements of pumpassembly 8, as illustrated in FIG. 1, is beneficial to understanding theoperation of each embodiment of the present invention. Generally, thepump assembly 8 will be implanted into the patient's scrotum. A separatefluid-filled reservoir (not shown) is implanted in some other portion ofthe patient's body, usually in the abdomen. Fluidly connecting thereservoir to the pump assembly 8 is fluid input 10 which will usually bea flexible silicone tube. A pair of inflatable cylinders (not shown) areusually implanted in the patient's corpus cavemosae and are fluidlyconnected to pump assembly 8 via fluid output 14, which is also usuallya flexible silicone tube.

In general, when pump assembly 8 is actuated, fluid is drawn from thereservoir through the pump assembly 8 and pumped into the cylinders.During the inflation process and until released by the patient, the pumpassembly 8 maintains the fluid pressure in the cylinders, thus keepingthem in their inflated state. When deflation is desired, the patientmanipulates assembly 8, permitting fluid to transfer out of theinflatable cylinders and into the reservoir, thereby deflating thecylinders and returning them to a flaccid state.

Pump assembly 8 generally includes a housing 12 usually formed ofsilicone. Attached to housing 12 is a pump bulb 18, which includes arelatively large pump chamber 36. Fluid input 10 is coupled to thehousing 12 and empties into a reservoir chamber 16. As such, fluid input10 couples reservoir chamber 16 to the reservoir. A common passageway 33is fluidly coupled to reservoir chamber 16 at one end of the housing 12,and is fluidly coupled to fluid output 14 at an opposite end of thehousing 12. Similarly, the pump chamber 36 is fluidly coupled to thecommon passageway 33 via pump passageway 34.

Disposed within common passageway 33 is a reservoir poppet 20 whichfunctions as a check valve. Reservoir poppet 20 is an elongated memberhaving a contoured portion which abuts reservoir poppet valve seat 24forming a fluid tight seal. A reservoir poppet spring 28 engagesreservoir poppet 20 and biases reservoir poppet 20 against the reservoirpoppet valve seat 24. Also disposed within common passageway 33 and inline with reservoir poppet 20 is cylinder poppet 22. Cylinder poppet 22forms a second check valve within common passageway 33. Cylinder poppet22 is biased by cylinder poppet spring 30 against cylinder poppet valveseat 26 in a normal state, thereby forming another fluid tight sealwithin common passageway 33. Reservoir poppet 20 is substantially longerthan cylinder poppet 22. A front end of reservoir poppet 20 extends intoreservoir chamber 16, in close proximity to an outer wall of housing 12.Furthermore, the front end of cylinder poppet 22 is in close proximityto the rear end of reservoir poppet 20. As such, the patient canmanipulate both poppets 20 and 22 by compressing the wall of housing 12.Compression of the housing 12 will cause the reservoir poppet 20 tocompress reservoir poppet spring 28 thus displacing the reservoir poppet20 from reservoir poppet valve seat 24. This motion will also causecylinder poppet 22 to be displaced from cylinder poppet valve seat 26while compressing cylinder poppet spring 30. When both reservoir poppet20 and cylinder poppet 22 are displaced from their respective valveseats, fluid is allowed to freely flow between reservoir chamber 16 andfluid output 14, and hence fluid is allowed to freely flow between thereservoir and the cylinders.

During a majority of the time, pump assembly 8 will be in theconfiguration shown in FIG. 1. That is, both reservoir poppet 20 andcylinder poppet 22 are abutting their respective valve seats 24 and 26,forming a fluid tight seal. When inflation is desired, pump bulb 18 ismanually compressed by the patient. This forces the fluid in pumpchamber 36 out through pump passageway 34 and into common passageway 33,under relatively high pressure. Because of the location of pumppassageway 34 with respect to the reservoir poppet 20, this increasedpressure causes reservoir poppet 20 to further abut reservoir poppetvalve seat 24. This increased pressure is more than sufficient to removecylinder poppet 22 from its abutment with cylinder poppet valve seat 26,by compressing cylinder poppet spring 30. As such, the pressurized fluidis allowed to pass through a portion of the common passageway 33 andinto fluid output 14, where it eventually reaches an inflatablecylinder. When released, the pump bulb 18 expands back to its originalconfiguration, creating negative pressure within pump chamber 36 andcommon passageway 33. This negative pressure draws cylinder poppet 22towards valve seat 26 and simultaneously pulls reservoir poppet 20 awayfrom valve seat 24. As such, fluid is drawn from the reservoir and intopump chamber 36 until the negative pressure is eliminated. Then,reservoir poppet spring 28 causes the reservoir poppet 20 to reseatitself against valve seat 24.

Repeated compression of pump bulb 18 eventually inflates the cylindersto a sufficient degree of rigidity for the patient. Once inflated, thefluid remaining in fluid output 14 is under a relatively high degree ofpressure. This high pressure fluid aids cylinder poppet spring 30 inforcing cylinder poppet 22 against cylinder poppet valve seat 26 againforming a fluid tight seal and preventing fluid from within thecylinders from passing through (preventing deflation of the cylinders).

When the patient desires deflation of the cylinders, the wall of housing13 is manually compressed. This compression forces reservoir poppet 20away from reservoir poppet valve seat 24 and simultaneously causescylinder poppet 22 to be removed from cylinder poppet valve seat 26. Thepressurized fluid within the cylinders and fluid output 14 naturallyreturns to the reservoir via common passageway 33. Furthermore, thecylinders can be manually compressed forcing out any remaining fluid.Once the cylinders are satisfactorily emptied, the patient releases thegrip on housing 12, thus allowing cylinder poppet 22 and reservoirpoppet 20 to once again abut their respective valve seats 24 and 26.

As described above, pump assembly 8 (as shown in FIG. 1) worksrelatively well under normal circumstances. However, when the patientcompresses the reservoir inadvertently through bodily movement, thepressure generated may be sufficient to remove reservoir poppet 20 andcylinder poppet 22 from their respective valve seats 24 and 26, thusspontaneously inflating the cylinders. When sufficient force isgenerated against the reservoir (or a similar component) to cause thefluid pressure to exceed the resistive characteristics of poppets 20 or22, an overpressure situation has occurred. Of course, the only way torelease this spontaneous inflation is to manually release the checkvalves.

To date, it has been very difficult to monitor and determine thepressures generated in an overpressure situation since each patientexhibits unique individual characteristics. Furthermore, eachspontaneous inflation may result from a very different physical act onthe part of the patient. However, it appears that pressure generated bycompression of the reservoir results in a fluid pressure of up to 3pounds per square inch (1.361 kg/25.4.sup.2 mm) but may be as high as6-8 pounds per square inch (2.722 kg/25.4.sup.2 mm). Conversely,compression of the pump bulb 18 will usually generate pressures on theorder of 20 pounds per square inch (9.072 kg/25.4.sup.2 mm).

Referring to FIG. 2, a first embodiment of the present invention isillustrated. A fluid input 10 couples a reservoir to reservoir chamber16. Reservoir poppet 20 has been modified to include a T-shaped tip 70.Tip 70 is secured to an outer reservoir chamber wall 72. Tip 70 issecured to the outer reservoir chamber wall by one or more connectingbands 74. Sufficient freedom of movement for reservoir poppet 20 isprovided so that during normal operation reservoir poppet 20 can bedislodged from its abutment with reservoir poppet valve seat 24.

During an overpressure situation, the reservoir is compressed,pressurizing the fluid and directing it through fluid input 10 and intoreservoir chamber 16. Outer reservoir chamber wall 72 has been madesufficiently flexible so that when this occurs, reservoir chamber 16 iscaused to expand due to the increased pressure generated. As outerreservoir chamber wall 72 expands, connecting bands 74 coupled with tip70 pull reservoir poppet 20 tightly against reservoir poppet seat 24.The overpressurization generated by the reservoir is used against itselfto prevent fluid from reaching the cylinders and creating a spontaneousinflation.

Referring to FIG. 3 a side partially sectional view is shown which helpsillustrate the interior side of outer reservoir chamber wall 72. Tip 70of reservoir poppet 20 is secured at each end by a connecting band 74which overlaps tip 70 and is interconnected with outer reservoir chamberwall 72. Any interconnection of tip 70 or reservoir poppet 20 to outerreservoir chamber wall 72 is acceptable so long as during anoverpressurization situation, reservoir poppet 20 is pulled againstreservoir poppet valve seat 24 and during normal use sufficientflexibility is provided so that reservoir poppet 20 can be displacedfrom reservoir poppet valve seat 24 allowing the desired fluid flow.

Referring to FIG. 4, a second embodiment of the present invention isillustrated. FIG. 4 illustrates the portion of housing 12 containingreservoir poppet 20 and cylinder poppet 22. Reservoir poppet 20 is anelongated member that terminates in a nose 82. A tapered reservoirpassageway 84 is provided through a sidewall 80 located adjacent tofluid input 10. Located at the junction of the sidewall 80 and reservoirpassageway 84 is a flap 78 that is able to flex, with respect tosidewall 80. Flap 78 is simply the terminus of sidewall 80 at thepassageway 84, and will optimally be offset by some angle from theremainder of the sidewall 80.

As illustrated in FIG. 4, reservoir poppet 20 is in a sealed position.That is, fluid is not able to pass from fluid input 10 through taperedpassageway 84 and beyond, because reservoir poppet 20 is sealed againstsidewall 80 at reservoir poppet valve seat 24 and is held in place byspring 28. In addition, nose 82 of reservoir poppet 20 contacts flap 78,providing a further seal. The remainder of passageway 84 is open betweenreservoir poppet 20 and sidewall 80.

In normal use, reservoir poppet 20 is pulled away from its sealedposition by a vacuum created at pump passageway 34. This allows fluid topass from fluid input 10, through passageway 84, and then through commonpassageway 33 into pump bulb 18. During a compression of pump bulb 18,reservoir poppet 20 is further pressed against valve seat 24.

During an overpressure situation, the fluid pressure in the reservoirand hence within fluid input 10 will increase. This increased pressureis applied evenly within fluid input 10, however flaps 78 are able togive in response to these forces. As such, flap 78 will be forcedagainst a portion of reservoir poppet 20. The shape of reservoir poppet20 and passageway 84 are chosen so that as flap 78 is pressed againstreservoir poppet 20, a strong seal is formed. In other words, sufficientgive is provided in sidewall 80, particularly at and behind flap 78 (dueto its shape and flexibility) so that increased pressure causes a fluidtight encasement of poppet 20 rather than a displacement of poppet 20.Therefore, reservoir poppet 20 remains sealed and spontaneous inflationis prevented. While one specific configuration of this concept is shownin FIG. 4, it is to be understood that a wide variety and combinationsof the disclosed teachings may be used while achieving the same result.The shape of the reservoir poppet 20, passageway 84, and the locationand shape of flap 78 are extremely variable so long as these elementswork together to form a fluid tight seal during an overpressuresituation.

Referring to FIG. 5, a third embodiment is illustrated. Reservoir poppet20 is an elongated member that extends from common passageway 33,through poppet passageway 92 and into fluid input 10. As with many ofthe above embodiments, in one position the reservoir poppet 20 abutsreservoir poppet valve seat 24. Similarly, reservoir poppet 20 is onlyexpected to be removed from valve seat 24 during a re-expansion of acompressed pump bulb 18. To prevent the removal of the reservoir poppetfrom valve seat 24 during an overpressure situation, relief area 90 hasbeen formed within the housing 12. Formation of relief area 90 creates aflexible valve 88. Flexible valve 88 forms a part of the reservoirpoppet valve seat 24, and appears as shown in FIG. 5, under normalcircumstances.

FIG. 6 illustrates an overpressure situation where the pressure of thefluid in fluid input 10 and poppet passageway 92 is relatively high.Rather than forcing reservoir poppet 20 from valve seat 24, thisoverpressure causes relief area 90 to expand; which in turn causesflexible valve 88 to even more firmly abut reservoir poppet 20.Depending upon the particular arrangement chosen, such an expansion ofrelief area 90 may cause some compression of reservoir poppet spring 28.In other words, reservoir poppet 20 is caused to move towards thecylinder poppet 22. Such motion will normally allow a spontaneousinflation to occur. However, in this embodiment, it is the movement ofvalve seat 24 that moves reservoir poppet 20, as such, a fluid seal isnot only maintained, it is made stronger. To further support reservoirpoppet 20, nose 46 of cylinder poppet is located in close proximity tothe rear of reservoir poppet 20. As such, when expansion of relief area90 causes a small amount of movement of reservoir poppet 20, reservoirpoppet 20 is caused to abut cylinder poppet 22. Therefore, any furthermovement of reservoir poppet 20 requires compression of both reservoirpoppet spring 28 and cylinder poppet spring 30. This combination ofspring forces provides a relatively high resistive force opposingfurther movement of reservoir poppet 20, even during an overpressuresituation. This combined with the expandable characteristics of reliefarea 90 prevents a spontaneous inflation from occurring. Of course, therelief area 90 can be fashioned to prevent such spontaneous inflationwithout causing the reservoir poppet 20 to engage cylinder poppet 22.

FIG. 7 illustrates a state where pump bulb 18 is being compressed,forcing fluid around cylinder poppet 22 and out through cylinder poppetoutput 32. Simultaneously, reservoir poppet 20 is forced towards fluidinput 10, causing flexible valve 88 to collapse against the innerportions of relief area 90. Once again, the strength of the seal atvalve seat 24 is increased during such movement.

Immediately after the state shown in FIG. 7 occurs, pump bulb 18 isreleased. As illustrated in FIG. 8, this creates a vacuum which pullscylinder poppet 22 against cylinder poppet valve seat 26 and pullsreservoir poppet 20 away from valve seat 24; thus allowing fluid fromthe reservoir to flow into pump bulb 18. Flexible valve 88 is createdwith sufficient rigidity to resist being forced against reservoir poppet20 while fluid is flowing through poppet passageway 92 and into pumpbulb 18. Furthermore, the previous compression of flexible valve 88against poppet 20 (FIG. 7) substantially evacuates relief area 90.Therefore when reservoir poppet 20 is initially pulled from valve seat24, relief area 90 will remain in an evacuated state while fluid flowbegins. The system is configured so that relief area 90 will not totallyfill (and expand) with fluid and seal against reservoir poppet 20 untilpump bulb 18 has been refilled. This can be done by making flexiblevalve 88 too rigid to allow such a seal to be formed in this state;providing for a sufficient amount of reservoir poppet 20 movement toprevent the flexible valve 88 from reaching poppet 20, even when reliefarea 90 is completely expanded; or simply imparting sufficient rigidityin flexible valve 88 so that the time is takes to expand relief area 90is greater than the time it takes to refill pump bulb 18.

FIG. 9 illustrates a fourth embodiment utilizing a combined solution toavoid spontaneous inflation. Namely, relief area 90 has been providedand works as described above. In addition, bypass passageway 38 has beenprovided which fluidly connects fluid input 10 to termination chamber40. Termination chamber 40 includes abutting wall 42, which acts as adiaphragm when an overpressure situation occurs. These two mechanismswill act in concert to prevent a spontaneous inflation from occurring.One advantage of this arrangement is that nose 46 of the cylinder poppet22 will be displaced towards the rear of reservoir poppet 20 via anexpansion of termination chamber 40. This force opposes the movement ofthe reservoir poppet 20, in the opposite direction that is generatedfrom an expansion of relief area 90. In essence, the force generated bythe overpressure is caused to directly oppose itself, which in turnprevents spontaneous inflation.

Referring to FIG. 10, a fifth embodiment to the present invention isillustrated. Housing 12 includes a fluid input 10 that is in fluidcommunication with fluid output 14 through a reservoir chamber 16 and acommon passageway 33. Common passageway 33 is selectively occluded by areservoir poppet 20 and cylinder poppet 22 which are both biased towardsa closed position. A portion of reservoir poppet 20 is physicallyconnected to a connection spring 100. The opposite end of connectionspring 100 is attached to a wall 13 of housing 12. Connections to spring100 are biased to maintain the configuration illustrated in FIG. 10.

FIG. 11 illustrates what occurs during an overpressurization situation.As increased fluid pressure is generated, wall 13 in reservoir chamber16 is caused to expand outward as indicated by the arrows. Sinceconnection spring 100 is fixedly attached to wall 13, the tensiongenerated by expanding spring 100 serves to pull reservoir poppet 20firmly against valve seat 24, creating an even more fluid tight seal.

Once pump bulb 18 has been compressed and released, vacuum forces aregenerated which unseat reservoir poppet 20. This situation isillustrated in FIG. 12. Thus, despite an overpressurization situationwherein wall 13 is expanded outwardly and connection spring 100 ispulling against reservoir poppet 20, the vacuum forces generated, aresufficient to unseat reservoir poppet 20 and allow fluid flow into pumpbulb 18 (as shown by flow arrows A).

When so desired, wall 13 is compressed causing reservoir poppet 20 tounseat itself and contact cylinder poppet 22 which, in turn, unseatsthat valve as well. Thus, fluid from the cylinders can be returned tothe reservoir. This situation is illustrated in FIG. 13 and illustrateshow the interaction of connection spring 100 and reservoir poppet 20will facilitate this movement.

Referring to FIG. 14, a sixth embodiment of the present invention isillustrated. A biasing spring 105, exerting a large amount of force, iscoupled to reservoir poppet 20 keeping it in its closed position.Because of the large amount of force being exerted, biasing spring 105will be able to resist high forces generated during anoverpressurization situation and, thus, preventing spontaneousinflation.

Because biasing spring 105 is significantly stronger than those in theprevious embodiments, it also makes it harder to open reservoir poppet20 with the level of vacuum forces generated by the pump bulb 18. Toovercome this issue, poppet face 110 is made significantly larger thanin the previous embodiments. That is, the surface area of poppet face110 has a diameter that approximates the diameter of intermediatechamber 107, which houses reservoir poppet 20. Though the amount ofpressure generated by the suction of release pump bulb 18 will be fixed,by increasing the surface area of poppet face 110, the negative forcegenerated will be greatly increased and will allow biasing spring 105 tobe overcome.

As illustrated, the portion of housing 12 in contact with poppet face110 when reservoir poppet 20 is closed, is not simply a planarconfiguration. As a practical matter, it is too difficult to manufacturea planar surface which will flushly and repeatedly coact with a planarpoppet face 110 to consistently form a fluid-tight seal. Instead, a pairof flexible lip seals is provided. That is, inner lip seal 115 and outerlip seal 120 are provided and define a recessed portion 125 betweenthem. Outer lip seal 120 contacts an outer portion of poppet face 110preventing suction forces from interacting with the rear portion ofpoppet face 110 and holding it in place during a refilling of pump bulb18. Inner lip seal 115 prevents fluid pressure generated during anoverpressurization situation from acting against a majority of poppetface 110, which would otherwise eliminate much of the benefit of havinga larger biasing spring 105. Lip seal 115 acting in conjunction with theforces generated by biasing spring 105 allows poppet face 110 to form afluid-tight seal despite any irregularities in either poppet face 110 orhousing 112. During an overpressurization situation, pressurized fluidfrom reservoir chamber 16 interacts with only a very small area ofpoppet face 110. The force generated will be insufficient to movebiasing spring 105, thus, reservoir poppet 20 will remain in the sealedposition preventing spontaneous inflation.

Referring to FIG. 15, a seventh embodiment of the present invention isillustrated. Once again, a reservoir poppet 20 and cylinder poppet 22are provided to selectively occlude a common passageway 33 between areservoir chamber 16 and a fluid output 14. As in the previousembodiments, a front face 150 of reservoir poppet 20 abuts valve seat 24to prevent fluid flow from reservoir chamber 16. In this embodiment thisoccurs in two different situations. That is during a compression of pumpbulb 18 (as illustrated in FIG. 16) and during an unused situation whenno overpressurization is occurring (as illustrated in FIG. 17).

Extending behind front face 150 is a rear section 137 of poppet 20. Atleast a portion of rear section 137 is hollow and is in fluidcommunication with throughbore 140 (a plurality of throughbores 140 canalso be provided). Outlet 145 forms a terminus of rear section 137 andis also in fluid communication with the hollowed out portion. A valvesleeve 130 slides over rear section 137 and is held in a spacedrelationship from front face 150 by slide spring 135 which biases frontface 150 away from valve sleeve 130. The movement of valve sleeve 130with respect to rear section 137 selectively seals and unsealsthroughbore 140.

As illustrated in FIG. 17, under normal conditions valve sleeve 130 isabutting a portion of housing 12. Slide spring 135 biases front face 150of poppet 20 against valve seat 24. In this situation, it is front face150 that prevents fluid flow from reservoir 16.

During an overpressurization situation, as illustrated in FIG. 15, theforces generated within reservoir chamber 16 serve to unseat front face150 causing it to move away from valve seat 24. To accomplish this,slide spring 135 must be at least partially compressed. In other words,overpressurization forces must be sufficient to compress slide spring135 to cause this to occur. As front face 150 is unseated, rear section137 moves through valve sleeve 130, since valve sleeve 130 is pressedfirmly against a portion of housing 12. This action causes throughbore140 to be occluded by valve sleeve 130. Therefore, even thoughpressurized fluid is able to enter into chamber 107, it is unable topass through valve sleeve 130 and enter throughbore 140. Consequently,pressurized fluid never reaches cylinder poppet 22 and is, therefore,unable to unseat it and cause spontaneous inflation.

During compression of the pump bulb 18 (FIG. 16), pressurized fluidenters intermediate chamber 107 forcing front face 150 to firmly abutagainst valve seat 24. At the same time valve sleeve 130 is pressedfirmly against its respective portion of housing 12. Since valve sleeveand front face 150 are spaced at their maximum distance, throughbore 140is exposed and pressurized fluid from pump bulb 18 is able to passthrough and unseat cylinder poppet 22 leading to an inflation of thecylinders.

FIG. 18 illustrates how a manual release of a reservoir poppet 20 canunseat both the reservoir poppet 20 and cylinder poppet 22 allowing fordeflation of the cylinders. Sleeve 130 is forced toward front face 150by the pressure in the cylinders once cylinder poppet 20 is unseated.

Referring to FIG. 18A, a poppet 20′ is disclosed that can alternativelybe incorporated into previous embodiments of the invention in place ofpoppet 20. The alternative poppet 20′ includes a plurality of flutes145′ that loosely correspond in function to the output 145 discussedpreviously. Similarly, the lower, curved ends 140′ of the flutes 145′loosely correspond in function to the throughbore 140 discussedpreviously.

Referring to FIGS. 19-22, an eighth embodiment of the present inventionis illustrated. Housing 12 includes common passageway 33 that fluidlycouples reservoir chamber 16 to fluid output 14 and is fluidly coupledto pump passageway 34. Housing 12 also includes a tapered reservoirpoppet valve seat 24 configured to interact with a similarly taperedfront face 210 of reservoir poppet 20. An annulus 205 is formed withinhousing 12 and is spaced away from, but proximate to, valve seat 24.Annulus 205 is configured to provide an opening 207 that is slightlysmaller than front face 210. Annulus 205 is a semi-rigid portion ofhousing 12 that allows passage of front face 210 through opening 207 bymoderate deflection. In other words, even though front face 210 isslightly larger than opening 207, it can still be forced therethrough.Comparing FIG. 19 with FIG. 21 also sees this relationship.

Housing 12 also includes a conical lip seal 200, which is positionedjust forward of cylinder poppet 22. Conical lip seal 200 is a flexiblemember that interacts with a stem 215 of reservoir poppet 20. Stem 215is generally cylindrical and includes a V-shaped groove 220 extendingaround its circumference. Groove 220 thus defines a medial stem section225 that lies between groove 220 and front face 210. Medial stem section225 is generally cylindrical.

Reservoir poppet 20 can be placed into three distinct configurationsthat define an activated state, a deactivated state, and a draining oropen state. In the activated state (FIG. 19), pump bulb 18 can be usedto inflate the cylinders. Reservoir poppet 20 is also maintained in theactivated state while the cylinders are to remain inflated. In thedraining state illustrated in FIG. 21, the cylinders can be emptied.Reservoir poppet 20 is placed in the deactivated state during periods ofnon-use to prevent spontaneous inflation.

FIG. 19 illustrates pump assembly 8 in the activated state. Front face210 is positioned between annulus 205 and valve seat 24. When sopositioned, reservoir poppet spring 28 biases front face 210 againstvalve seat 24. If pump bulb 18 is compressed, the fluid pressuregenerated reinforces the biasing action of reservoir poppet 20, andcauses front face 210 to further abut valve seat 24. At the same time,cylinder poppet 22 is unseated and fluid is forced into the cylinders.When reservoir poppet 20 is so positioned, V-shaped groove 220 isaligned with conical lip seal 200. This effectively prevents conical lipseal 200 from interfering with fluid flow in either direction. That is,the configuration of conical lip seal 200 is such that it cannoteffectively prevent fluid flow in a direction from cylinder poppet 22towards reservoir chamber 16. Fluid flow in the opposite direction isalso unhindered (in the activated state) because groove 220 permitsfluid pressure levels to increase “underneath” conical lip seal 200(i.e., between lip seal 200 and stem 215), thus fluid flow is permittedfrom pump chamber 36 to the cylinders. FIG. 19 illustrates thisconfiguration during a compression of pump bulb 18.

FIG. 20 illustrates the configuration of the components during a releaseof pump bulb 18. The vacuum generated works with the biasing force ofcylinder poppet spring 30 to cause cylinder poppet 22 to seal. Thevacuum forces also cause front face 210 to be pulled away from valveseat 24. This allows fluid to flow from reservoir chamber 16 into pumpchamber 36. While the vacuum forces are sufficient to unseat front face210, they are insufficient to cause it to pass through annulus 205;thus, back face 211 of reservoir poppet 20 abuts annulus 205 or(depending on the spring forces involved) is held between annulus 205and valve seat 24. In either case, fluid as able to flow into pumpchamber 36. After a number of compressions of pump bulb 18, the cylinderwill be inflated. While the cylinders are to remain inflated, pumpassembly 8 is kept in the activated state.

During a release of pump bulb 18, the vacuum forces generated may besufficient to cause back face 211 to seal against annulus 205. If thisoccurs, the pump assembly may lock up and remain in this position. Thatis, pump bulb 18 will be at least partially compressed and the vacuumgenerated will be sufficient to keep reservoir poppet 20 sealed againstannulus 205, preventing fluid from moving from the reservoir to pumpchamber 36. All that need be done to relieve the vacuum is manuallycompress the sidewall to cause reservoir poppet 20 to unseat.

This situation may be confusing to patients and they may not realize thenature of the problem. Thus, a modified annulus 205 (and/or a variationin reservoir poppet 20) can be provided to prevent the situation fromoccurring. Referring to FIGS. 20A and 20B, such a modified annulus 205is illustrated. Annulus 205 includes a number of spacers 213 positionedabout annulus 205 and facing valve seat 24. Spacers 213 are positionedso that when rear face 211 is in contact with them, there is still afluid path around reservoir poppet 20 and through annulus 205. That is,there is never an opportunity for rear face 211 to seal against annulus205.

The nature and number of spacers 213 can vary. Providing three spacersallows full support of rear face 211. That is, rear face 211 is notcaused to pivot by only being supported at one or two points. Thispivoting action is not necessarily detrimental, and one or two spacers213 could be utilized. More could also be utilized, so long assufficient fluid flow is permitted. The actual size and shape of spacers213 will depend upon the methods utilized to form them. Any size, shapeand configuration is permissible so long as fluid flow sufficient toprevent the above described vacuum lock is permitted. Finally, spacers13 could be attached to rear face 211 rather than annulus 205 to permitappropriate fluid flow.

Alternatively, various other methods could be employed to achieve thesame result. So long as fluid flow around rear face 211 and throughannulus 205 is permitted, this potential problem is avoided. There aresolutions other than providing spacers. For example, one or more groovescould be cut into rear face 211 to achieve the same result. Variousother access ports or passageways could likewise be provided. Of course,these various techniques could be combined in any number of ways.

After use, when the operator wishes to deflate the cylinders, thesidewalls of housing 12 are compressed. This forces reservoir poppet 20to move from the activated position, past the deactivated position (asshown in FIG. 22) and into the draining state, by causing front face 210to move through annulus 205 to the position illustrated in FIG. 21.Furthermore, this movement of reservoir poppet 20 causes it to engagecylinder poppet 22 and unseat it as well as moving front face 210 awayfrom annulus 205. Fluid is then able to flow from the cylinders into thereservoir.

When the cylinders are satisfactorily deflated, housing 12 is released.Referring to FIG. 22, reservoir poppet spring 28 biases front face 210against annulus 205. As shown, reservoir poppet 20 is in the deactivatedposition. In this position, conical lip seal 200 engages medial stemsection 225, which is cylindrical in nature and approximates conical lipseal 200 in size and shape. Should a compression of the reservoir causean overpressure situation, increased fluid pressure will force reservoirpoppet 20 to be moved back from annulus 205 and allow reservoir pressureto enter intermediate space 300. Without lip seal 200, reservoirpressure would enter common passageway 33 and open cylinder poppet 22causing spontaneous inflation. However, reservoir pressure will act onconical lip seal 200 causing it to firmly seal against medial stemsection 225, thus preventing fluid pressure from acting on cylinderpoppet 22 and thus preventing spontaneous inflation.

The operator must place pump assembly 8 in the deactivated state duringperiods of non-use to effectively prevent spontaneous inflation. Whenthe operator desires to inflate the cylinders and pump assembly 8 is inthe deactivated state, all that is required is a compression of pumpbulb 18. As pump bulb 18 is compressed, fluid pressure levels withinintermediate space 300 are rapidly increased to relatively high levels.Conical lip seal 200 continues to prevent fluid flow therethrough (thuspreventing an unseating of cylinder poppet 22); however, the higherpressures being generated are sufficient to force front face 210 throughannulus 205. Thus a compression of pump bulb 18 causes reservoir poppet20 to move from the deactivated position to the activated position, fromwhich the cylinders are inflated in the above described manner.

FIGS. 23-28 illustrate alternative embodiments of a reservoir poppet 318and a pump and valve assembly 300 in which certain modifications havebeen made to improve performance. The functionality and operability ofthe arrangement of FIGS. 23-28 is discussed in co-pending applicationSer. No. 09/749,075 entitled “Penile Pump With Side Release Mechanism”which was filed on Dec. 27, 2000, and Ser. No. ______ entitled “ImprovedPenile Pump With Side Release Mechanism,” (Attorney-Docket No. AMS-040)filed concurrently herewith, the entire disclosure of which is hereinincorporated by reference.

As shown in FIG. 23A, a reservoir poppet 318 comprises an elongate rigidmember 260 and a synthetic member 262. Synthetic member 262 is disposedover a segment/post portion 264 of the rigid member 260. Rigid member260 is preferably made of a metal material, such as steel, stainlesssteel, or the like. Synthetic member 262 is preferably made of a strong,durable plastic material, for example, acetal, nylon and/or polyester,to prevent undesired frictional contact with another metal member, suchas an actuating bar described below. Synthetic member 262 is rigidlyattached to rigid member 260 by molding, bonding, or the like. Syntheticmember 262 prevents premature wearing of reservoir poppet 318 andanother member. For example, synthetic member 262 may prevent directmetal-on-metal contact of metal reservoir poppet 318 with an actuationbar 310, as shown in FIG. 24. The addition of synthetic member 262reduces the frictional interaction of reservoir poppet 318 and anothermetal member, which typically occurs at an end 266 of reservoir poppet318. Thus, the risk of marking or deforming reservoir poppet 318 and theengaging metal member is reduced, and the useful life of the twocomponents is extended.

As disclosed in the embodiments of FIGS. 19-22 above, V-shaped groove220 is sized and shaped to operably associate with lip seal 200 toprevent lip seal 200 from interfering with fluid flow at predeterminedrelationships between the poppet 318 and lip seal 220. As shown in theembodiment of FIG. 23B, poppet 318 has a poppet taper 777. In operation,when poppet 318 is pushed back into the release or deflation mode (seeFIG. 26C), taper 777 permits lip seal 200 to separate from poppet 318.This allows fluid from the cylinder to pass unimpeded through the pump.Without taper 777, lip seal 200 would rest on reservoir poppet 318 asshown in FIG. 23C. The arrangement of FIG. 23C requires pressure to openlip seal 200 before fluid is allowed to pass from the cylinder to thereservoir. Moreover, when the pressure drops below a minimum value, lipseal 200 closes on poppet 318 and traps pressurized fluid in thecylinder. This typically happens at a less than flaccid cylindercondition. Unfortunately, to force this pressurized fluid out of thecylinder when it is at this state, the patient must squeeze his penisand the cylinder to increase cylinder pressure and open the lip sealdesign. For these reasons, the embodiment shown in FIG. 23C is a lesspreferred design.

As discussed in the embodiments above, in some patients it may bedifficult to achieve compression because of the relatively small size ofpump bulb 18. Likewise, it may be difficult for certain patients tograsp valve housing 12 in the proper manner since valve housing 12 mayslip out of position between the patient's fingers. Thus, an alternativepump and valve assembly 300 is provided as shown in FIGS. 24-28.

FIG. 24 shows an exploded view of the alternative pump and valveassembly 300 with an actuating bar 310, a pump bulb 316, a reservoirpoppet 318, and a poppet support 320. Assembly 300 comprises a valveblock 317 for housing the fluid passageways that inter-connectinflatable cylinders and a reservoir (not shown), as discussed in theembodiments above. Actuating bar 310, having a plurality of ribs 328 and330, attaches to a side of valve block 317 and is positioned to engagean end of a reservoir poppet 318. Reservoir poppet 318 is a check valvethat operates to control fluid flow into and out of a reservoir, and isto be positioned within fluid passageways of valve block 317. Poppetsupport 320 is to be disposed on an end of valve block 317, proximate anend 266 of reservoir poppet 318, to prevent sideways sliding ofreservoir poppet 318 during actuation of the pump. Pump bulb 316 is tobe located over the valve block 317, actuating bar 310, reservoir poppet318, and poppet support 320. Pump bulb 316 comprises major panels 312and 314 with textured surfaces that allow patients to easily identifythat portion of the valve assembly 300. When a patient applies pressureto major panels 312 and 314 of pump bulb 316, major panel 312 engagesactuating bar 310. This allows the patient to grasp the major panels 312and 314 to cause actuating bar 310 to force reservoir poppet 318 to moveto an open position, permitting the flow of fluid through the channelsof valve block 317. Actuating bar 310 and poppet support 320 aredescribed in detail below.

Preferably, reservoir poppet 318 of the embodiment of FIG. 24 issubstantially the same as hybrid metal and synthetic reservoir poppet318 disclosed in FIG. 23A and discussed above.

As illustrated in FIGS. 24-26, actuating bar 310 is a thin elongatedmember formed to comprise an actuating face 322 and an actuating arm 324that are connected by an angle portion 326. A U-shaped portion 332connects a connecting end 338 to actuating face 322.

Connecting end 338 includes two forked portions 666, one of which isshown in FIG. 25. As shown in FIG. 26A, actuating bar 310 is disposedwithin valve block 317 by securement of end 338 into a valve blockinterface 336. The forked portions 666 of connecting end 338 help holdactuating bar 310 in place.

Angle portion 326 provides actuating bar 310 with a spring force that isapplied to an end 266 of reservoir poppet 318. Angle portion 326 permitsactuating face 322 of actuating bar 310 to extend along the length ofvalve block 317 while actuating arm 324 extends along a side of thewidth of the valve block 317. The configuration of actuating bar 310enables it to engage an end 266, e.g., the tip, of reservoir poppet 318.Actuating arm 324 includes a curved portion 325 for complementaryengagement with reservoir poppet end 266. Preferably, curved portion 325presents a smooth face to the side of the pump shell when the pump shellacts on the curved portion 325 of the actuating bar 310.

As discussed above, when the patient grasps the valve assembly invirtually any orientation and applies pressure (e.g. see FIG. 26C),actuating bar 310 acts to open the appropriate check valves. Thus, whenthe patient grasps a portion of the pump and valve assembly 300 otherthan the pump bulb 316, compression will result in the flexing ofactuating bar 310. During compression, actuating face 322 flexesinwardly and actuating arm 324 flexes toward poppet end 266, asindicated by arrow A in FIG. 26A. Actuating arm 324 moves intoengagement with poppet end 266. The movement of actuating arm 324 forcesaxial movement of reservoir poppet 318 in the same direction as arrow Aand into an open position. The axial movement of the reservoir poppet318 permits fluid to flow through the fluid pathways to the reservoirand allows the cylinders to deflate (FIG. 26C).

When the patient ceases compression of pump and valve assembly 300,actuating face 322 returns to its original position. Actuating arm 324moves in a direction indicated by arrow B, and out of engagement withpoppet end 266. This motion permits reservoir poppet 318 to move intothe deactivated position, as shown in FIG. 26A.

Angle portion 326 in actuating bar 310, and its resistance to flexingoutwardly, creates a desirable spring force member. This spring is themechanism that forces reservoir poppet 318 into a position that permitsthe flow of fluid through the fluid pathways and back into thereservoir. For example, during patient compression of pump and valveassembly 300 (FIG. 26C), actuating arm 324 enters engagement with poppetend 266. Actuating arm 324 applies the spring force to the poppet end266 to force reservoir poppet 318 into the interior of valve block 317into an open position. When actuating arm 324 is engaged with poppet end266, there is an opposing force created by the resistance of reservoirpoppet 318 to movement toward the open position. This opposing force mayovercome the spring force and cause actuating arm 324 to improperlydeflect. Stated alternatively, this improper deflection occurs when theopposing force exerted against the spring force of actuating bar 310overcomes the inherent spring force and causes the actuating arm 324 tobend backwards or buckle.

To prevent improper deflection, ribs 328 are formed on actuating bar310, as shown by FIG. 25. Each rib 328 is a recess or impression formedin actuating bar 310 and extends across angle 326. Ribs 328 increase thestrength and stiffness of angle portion 326, which increases theresistance to deflection during actuation. The surface area of angleportion 326 is disposed along a given plane. Ribs 328 divide the surfacearea of angle portion 326 with recesses that extend into another plane.The portions of material extending in a different plane increase thespring force of angle portion 326. This increase in spring forcedecreases the likelihood of improper deflection of actuating arm 324.The absence of improper deflection thus ensures full axial travel ofreservoir poppet 318 and attainment of the open position. Additionally,reinforcement of angle portion 326 prevents any permanent deformationthat might occur due to repeated actuation. This resistance todeflection or bending helps prevent fatigue of actuating bar 310 andextends the useful life of the component. Although ribs 328 may beformed by a curved recess that extends in a plane perpendicular to thesurface of angle portion 326 as shown in the Figures, ribs 328 may existin many different orientations. A sufficient number of ribs 328 may beprovided to angle 326 so as to achieve a predetermined deflectionresistance. For example, two ribs 328 are provided in the angle 326, asshown in FIG. 25.

When a patient compresses valve assembly 300 to deflate the prosthesis,actuating face 322 flexes or pivots inwardly about U-shaped portion 332.This causes actuating face 324 to move into engagement with poppet end266. The repeated application of force to a particular area of actuatingface 322, may cause permanent deformation. As shown in FIG. 25, a recessformed in and disposed along actuating face 322 defines a rib 330. Rib330 strengthens and stiffens actuating face 322 to limit deformation.Rib 330 extends into a plane other than the plane created by the surfaceof actuating face 322 to increase its resistance to bending. Duringpatient compression, rib 330 distributes the force applied throughoutactuating face 322 rather than permit the compression force to beconcentrated in one area. Thus, actuating face 322 properly flexes whileresisting permanent deformation. Rib 330 may be shaped to distribute thecompression force in any desired pattern. For example, as shown in FIG.25, rib 330 may be a spoon-shaped impression centrally formed onactuating face 322 with a larger oval portion disposed toward U-portion332 of actuating bar 310. An elongate portion 334 of spoon-shaped rib330 extends toward angle portion 326. This shape is preferred since rib330 helps to lower stresses and reduce deflection caused by compressionforces applied to flex actuating face 322.

The relatively thin composition of actuation bar 310 is beneficial forseveral reasons. During actuation, U-portion 332 bends to flex actuatingface 322 inwardly and actuating face 322 moves actuating arm 324 intoengagement with reservoir poppet 318. After actuation, U-portion 332,actuating face 322 and actuating arm 324 return to their originalposition. With an actuating bar made of a thick material, U-portion 332does not properly bend during actuation. In operation, when using athicker actuating bar 310 U-portion 332 does not bend, and connectingend 338 is pushed into valve block 317 causing its inner cavities todistort. In turn, this causes annular ring 500 (FIG. 26) of valve block317 to come out-of-round and impedes or stops the movement of poppet 318in direction A. Preferably, actuating bar 310 is a thin member made of amaterial with a sufficient thickness and stiffness to provide thedesired spring force and avoid improper deflection. For example,actuation bar 310 may be formed from a stainless steel sheet having athickness of approximately 0.010 inches. Actuation bar 310 may be madeof various metal materials, plastic, or the like.

As shown in FIG. 26C, the engagement of actuating arm 324 and poppet end266 can be applied from one side of reservoir poppet 318. Thus, thespring force applied by actuating bar 310 is not completely along alongitudinal axis of reservoir poppet 318. The spring force is appliedin both the axial and transverse/sideways directions to poppet end 266.The sideways force has the unintended consequence of tipping reservoirpoppet 318 sideways into valve block 317. In response, valve block 317tends to deform and potentially causes reservoir poppet 318 to bemisaligned. This misalignment results in reservoir poppet 318 beingrestrained from moving axially into valve block 317 to reach anactivated/open position. As shown in FIGS. 26A-28, a stiff poppetsupport 320 is provided to prevent the misalignment of reservoir poppet318.

As shown in FIG. 27, poppet support 320 is an elongate, generallyL-shaped member comprising a shelf 342 at one end of poppet support 320.Apertures 344 are provided in a portion of support 320 to attach thesupport 320 to valve block 317. See FIGS. 26 and 27. The poppet support320 wraps around a portion of the valve block 317 and rests against aportion of poppet end 266. The shelf 342 provides a smooth surface for asegment of reservoir poppet 318 to slide axially along during reservoirpoppet 318 travel between open and closed positions. During actuation,curved portion 325 of actuating bar 310 applies a spring force,comprising both axial and side forces, to move reservoir poppet 318 toan open position. Poppet support 342 prevents sideways movement of thereservoir poppet 318 as it is forced into the interior of the valve body317. Poppet support 320 ensures the proper alignment of reservoir poppet318 to easily move axially into valve body 317 to the open position.

Various embodiments have been shown and described to prevent spontaneousinflation. It is to be understood that though these embodiments havebeen shown and described in isolation, various features of eachembodiment can be combined with the others to produce a variety ofembodiments.

While the present invention has been described with respect to a pumpand valve assembly for a penile implant, the use of generatedoverpressure to seal a fluid aperture has many other applications withinthe scope and spirit of the present invention. For example, artificialsphincters utilize fluid pressure to maintain a body cavity or naturalpassageway in a closed or sealed state. When actuated, fluid pressure isreleased from the sphincter, causing the bodies' passageway to open. Assuch, the fluid pressure generated could be used to assist theartificial sphincter in either state. Likewise, many other uses for anoverpressure seal exist, both specifically within the field of medicaldevices and within the field of fluid/gas handling devices in general.

Those skilled in the art will further appreciate that the presentinvention may be embodied in other specific forms without departing fromthe spirit or central attributes thereof. In that the foregoingdescription of the present invention discloses only exemplaryembodiments thereof, it is to be understood that other variations arecontemplated as being within the scope of the present invention.Accordingly, the present invention is not limited in the particularembodiments which have been described in detail therein. Rather,reference should be made to the appended claims as indicative of thescope and content of the present invention.

1. A method of preventing inadvertent inflation of an implantableprosthetic comprising the steps of: biasing a valve assembly such thatan outlet is substantially closed; and using inadvertent pressureincreases from the inlet to supplement the biasing of the valveassembly.
 2. The method of claim 1, wherein the step of usinginadvertent pressure includes: preventing fluid flow through the outletby selectively varying fluid pressure within a bypass passageway havinga first end which is in fluid communication with an inlet and a secondend which is in fluid communication with a chamber.
 3. The method ofclaim 2, further comprising the steps of: displacing a flexible abuttingwall disposed between the chamber and the valve assembly so that theabutting wall is caused to contact the valve assembly and urge the valveassembly into a closed position when the fluid pressure within thechamber exceeds a predetermined amount.
 4. The method of claim 2,further comprising the steps of: sliding a valve sleeve along a rearportion of the valve assembly to occlude a passageway leading through aportion of the valve assembly and to sealingly engage a portion ofhousing.
 5. A method of preventing inadvertent inflation of animplantable prosthetic comprising the steps of: biasing a valve assemblysuch that an outlet is substantially closed, wherein a biasing mechanismis sufficiently strong to oppose increased pressure levels generatedduring an overpressurization situation; providing a sufficient surfacearea on the valve assembly so that vacuum forces generated after acompression of a pump bulb are sufficient to open the valve assembly. 6.A method of preventing a vacuum lock from occurring in a penileprosthesis having a valve movable through an annulus so that when on afirst side of the annulus operation of the prosthesis is permitted andwhen on a second side, spontaneous inflation is prevented, comprising:positioning the valve on the first side of the annulus; and providing afluid path around the valve through the annulus when a rear face of thevalve is proximate the annulus.
 7. The method of claim 6 including thestep of: providing at least one spacer to prevent the rear face fromsealing against the annulus.
 8. The method of claim 7 including the stepof: providing at least one spacer that is integral with the annulus. 9.A method of preventing inadvertent inflation of an implantableprosthetic comprising: biasing a valve assembly such that an outlet issubstantially closed, wherein a biasing mechanism is sufficiently strongto oppose increased pressure levels generated during anoverpressurization situation; providing a support mechanism mechanicallylinked to the valve assembly to prevent sideward movement of a valvewhen moving between an open and a closed position; and providing asufficient surface area on the valve assembly so that vacuum forcesgenerated after a compression of a pump bulb are sufficient to open thevalve assembly.